Life actually: ‘I don’t do unshaven – makes me look like someone about to have a breakdown,’ says Bill Nighy. Photograph: Alex Lake for the Observer

Bill Nighy has suggested we meet in Notting Hill, in a café run by an Italian family who really know their coffee. His ritual is to come here for an espresso on his way to his favourite Indian restaurant nearby, where he likes to sit and eat on his own while reading a book. But even if he wasn’t a regular here, I suspect he would still be recognised by the waiters, because he never tries to disguise himself in public. On the contrary, he always seems to look like someone doing an impersonation of Bill Nighy.

It’s to do with his black-framed glasses and the bespoke navy suits he wears over open-necked shirts. Today he arrives in an overcoat and midnight-blue silk scarf with white polka dots, which also seems very Bill Nighy. He wears these elegant clothes well, but doesn’t he ever feel like dressing more casually? Putting on a T-shirt and jumper? “Actually,” he says in that mellow and unhurried voice of his, “I never wore T-shirts even when I was supposed to wear them. Never felt I had the right shape. Couldn’t do a T-shirt justice. And I don’t do unshaven well either. It makes me look like someone about to have a breakdown.”

He is keenly aware of his own absurdities, which not only include his sartorial “fetishism” (his word) but also a fairly manic obsession with football (in general and Crystal Palace in particular), and music (again in general, but especially Bob Dylan and the Rolling Stones). He can’t help it; he has a compulsive nature – one that, like his professed “crippling self-consciousness”, seems to be at odds with the insouciance and languor of his public persona.

But does he ever catch himself stepping into a sort of Bill Nighy character when he leaves his house, playing up to people’s expectations? “Not really, no. I always assume when I meet people in the street that they are going to be basically disappointed. But there’s, what’s the word? There’s no... what is the word? No conflict. There’s no conflict between the private me and the public me.”

The public him, the actor, has had a career that can be divided into two halves. The first got off to a wobbly start. Struggling to find work in the early 70s, he gave up acting and took a job on a market stall in Croydon selling women’s clothes. “Then someone put me up for an audition at the Everyman in Liverpool and my life changed.” The Everyman – where the resident writers were Willy Russell and Alan Bleasdale – was a hotbed of socialism and agitprop. That must have been a shock to his system, given that his father, who ran a small garage in Caterham, Surrey, was a Tory.

“Yes, I was a mess of anxiety and general unease,” he says. “I had somehow managed not to learn the difference between Left and Right, and when I got to the Everyman it was too late to ask. I took the Times in one day and the director took it off me and threw it across the room in disgust.”

From the Everyman he progressed to the National Theatre, where he worked with David Hare, Tom Stoppard and Harold Pinter. But this wasn’t a happy period in his life. Wracked with insecurity about work and money, and suffering from chronic stage fright, he developed an “unhealthy relationship” with alcohol, a dependence he wasn’t to kick until 1992. To this day he still doesn’t like to talk about it.

Then in 2003, at the age of 53, he became highly bankable almost overnight when he won two Baftas, one for playing a newspaper editor in the TV drama State of Play, and another for his role as a washed-up but endearing rock star in the Richard Curtis romcom Love Actually. He appreciates what that film did for him (not least that it got him out of ever having to do an audition again), but he is a bit scratchy about people assuming that his acting career began that year. “I did go through a phase of politely pointing out that I had been around as an actor for a long time before that.”

One legacy of the first half of his career was that he found it hard to turn work down when the second half began. He has averaged three or four films a year since, but has become choosier lately. And his bankability as a film star has meant he can also afford to take up offers of theatre work when the mood takes him. His recent West End performance opposite Carey Mulligan in a revival of David Hare’s Skylight won him much acclaim, and he enjoyed doing it so much he is about to head off to Broadway to do it again, for a four-month run.

The play is set in the post-Thatcher early 90s, and as with all David Hare plays, there are some comic lines in it. There is also an anti-Thatcherite political message – one with which, you suspect, Nighy agrees. Although he doesn’t like to align himself with any one party, his politics are broadly on the Left, and if you want to get him on the subject of the Robin Hood Tax, which is a levy on financial transactions, you should settle down for a half-hour lecture. He lobbies about it on behalf of Oxfam at G8 summits.

But the reason members of the public always approach him as if they know him, as if he is an old friend, is not because they expect a lecture on politics. It’s because they think he will make them smile. And it is easy to see how they might confuse him with the parts he plays: all those amusing tics and mannerisms you see on film are his, as is that hesitant voice and delivery. It can all seem like self-parody when you meet him in person.

One of the first things you notice about Bill Nighy is his hands. He suffers from Dupuytren’s contracture, a condition that causes some of his fingers to bend in towards the palm, which can make shaking hands with fans difficult. Does it hurt? “Not at all. It started in my 20s. It was alarming and I should have had an operation on them at the time, but I didn’t because I was a mess and was frightened.” He holds up his left hand. “It means I have a spooky handshake.”

The hands have become part of what makes him distinctive as an actor, affecting as they do the way he moves and holds himself, so much so that some young actors assume it is an affectation. “They come up to me and say: ‘I like that thing you do with your hands.’”

The hands are, as it were, something he has to bring to every role, and they make him an easy target for mimicry. I came across a sketch online in which Harry Enfield plays Bill Nighy playing Hugh Grant in a Richard Curtis romcom. It’s all “Gosh!” and “What a clot!” and it is cruelly well observed, not least because Nighy always seems to play a version of himself in Richard Curtis films, notably The Boat That Rocked (2009) and About Time (2013).

He is aware of this, and does sometimes go out of his way to avoid it, as he did for last year’s Pride, a film about a group of gay activists who supported the miners during their strike. Not only did he look different in that, with his slicked-down hair, but he sounded very different, too: Welsh, in fact. (“To get the accent right,” he says, “I went down to Wales and hung about in pubs with a tape recorder asking people to speak my lines.”) But even in Pirates of the Caribbean, when he was speaking with a Scottish accent and had his face obscured by octopus legs, Bill Nighy was still unmistakably Bill Nighy.

In his latest film, The Second Best Exotic Marigold Hotel, out this month, he is very much back to playing an absent-minded and charming adaptation of himself. It is a follow-up to The Best Exotic Marigold Hotel, which was a surprise box-office hit in 2011 (surprise because it was about old people setting up a retirement home in India). The sequel has all the warmth and gentle humour of the first and sees Nighy riding around Jaipur on a motorbike with Dame Judi Dench on the back for the second time. “I’m still hopeless on a motorbike,” he says. “Took 17 takes. I don’t know why they didn’t use a stunt rider in long shot.”

Does he imagine he will end up in a retirement home like that one day? “I’m hoping not to retire. What do we hope for? Go to bed and don’t wake up, I suppose.” Actually, he contemplates mortality much more than this glib answer would suggest. “I probably think about death 12 times a day,” he says. “I measure my life in Champions Leagues. How many do I have left?”

But he also has other ways to fill his days. “When I’m working I have to get up at five, so when I’m not I like to get up at 10,” he says. “I put on some John Lee Hooker, shave, then go round to the café for a leisurely breakfast with two football pages. Then I go to the bookshop for a browse. Then I drink coffee very slowly in a café near Berkeley Square.”

He has a thing for Berkeley Square. “I love studying the plane trees. They overwhelm me. As you get older you feel you need to pay more attention to what is around you and relish it. I’m greedy for beauty.” He concedes that his perfect day is really “wandering about London on my own. I built my life around not being in a hurry.”

And in the evening? “In the evening I like to eat in an Indian restaurant on my own and then go home and watch football matches. I have Sky Plus-ed. I record the whole season. The Spanish league, too.”

For 23 years he lived with the actor Diana Quick, the mother of his daughter Mary (who is also an actor, and director, and to whom Nighy is close). But the couple separated in 2008 and nowadays he seems to prefer his own company. Or at least I think he does. Is there someone he comes home to? “No, Nigel,” he says, his mouth a horizontal slab, twitching at the corners. “I don’t come home to anyone. I live alone, and if I was in a relationship and I were to tell you about it I would involve your readers in something approaching gossip, and I know they would never forgive me for that.”

What about friends? Sounds a bit lonely, this day he has described. “I do have friends, honestly I do have some, but I sort of enjoy my own company and I don’t do that thing of: ‘Let’s all get together.’ I would never throw a party. Wouldn’t know whom to invite.”

Richard Curtis? David Hare? Dame Judi? “I suppose. Maybe. Maybe it would be more of a dinner party. I did once give a dinner party. But it was a long time ago and it won’t happen again.”

A poignant note on which to end. It is time for the spooky parting handshake. He retrieves his scarf, exchanges a few friendly words with some members of the public who have recognised him, and heads outside to wander about on his own and stare at trees.